The interaction of TbC13 and lanthanide（Ⅲ） β-diketonate complexes with poly（N-vinylpyrrolidone） （PVP） polymer was studied using fluorescence spectroscopy. In the presence of PVP the emission of Tb3＋ in cthano...The interaction of TbC13 and lanthanide（Ⅲ） β-diketonate complexes with poly（N-vinylpyrrolidone） （PVP） polymer was studied using fluorescence spectroscopy. In the presence of PVP the emission of Tb3＋ in cthanolic solution of TbCl3 significantly in- creased owing to the excitation energy transfer from PVP to Tb3＋ ions, which was more efficient as compared to a direct excitation of the Tb3＋ 4f75d1 levels. In contrast, emission of NEt4Tb（hfa）4 and NEt4Eu（hfa）4 complexes was almost completely quenched in solu- tion containing PVP. The PVP bound both Ln3＋ ions and hfa ligands which caused decomposition of Ln-hfa complexes and switched off the excitation energy transfer from the ligand to the emitting Ln3＋ ion. The important role of hydrogen bonds in stabilization of in- teraction ofhfa ligands with PVP was indicated.展开更多
Following the experimental realization of Quantum anomalous Hall(QAH)effect in thin films of chromium-doped(Bi,Sb)2Te3,enhancing the work temperature of QAH effect has emerged as a significant and challenging task.Her...Following the experimental realization of Quantum anomalous Hall(QAH)effect in thin films of chromium-doped(Bi,Sb)2Te3,enhancing the work temperature of QAH effect has emerged as a significant and challenging task.Here we demonstrate monolayer TbCl as a promising candidate to realize the room temperature QAH effect.Using DFT+U method,double-checked by HSE06 and DMFT calculations,we identify the Hall conductivity G=−e^(2)/h per layer in three-dimensional ferromagnetic insulator TbCl,which is a weakly stacked QAH layer.The monolayer TbCl inherits the magnetic and topological properties,exhibiting the QAH effect with Chern number C=−1.The large topological band gap reaches 42.8 meV,which is beyond room temperature.The extended 5d electrons lead to sizable exchange and superexchange interactions,resulting in a high Curie temperature T_(c)-457 K.All these features demonstrate that monolayer TbCl will provide an ideal platform to realize the room temperature QAH effect.展开更多
文摘The interaction of TbC13 and lanthanide（Ⅲ） β-diketonate complexes with poly（N-vinylpyrrolidone） （PVP） polymer was studied using fluorescence spectroscopy. In the presence of PVP the emission of Tb3＋ in cthanolic solution of TbCl3 significantly in- creased owing to the excitation energy transfer from PVP to Tb3＋ ions, which was more efficient as compared to a direct excitation of the Tb3＋ 4f75d1 levels. In contrast, emission of NEt4Tb（hfa）4 and NEt4Eu（hfa）4 complexes was almost completely quenched in solu- tion containing PVP. The PVP bound both Ln3＋ ions and hfa ligands which caused decomposition of Ln-hfa complexes and switched off the excitation energy transfer from the ligand to the emitting Ln3＋ ion. The important role of hydrogen bonds in stabilization of in- teraction ofhfa ligands with PVP was indicated.
基金supported by the National Key Research and Development Program of China(2024YFA1611200)the National Natural Science Foundation of China(Grant No.12274154,12404182)The computation is completed in the HPC Platform of Huazhong University of Science and Technology.J.Y.Zou also thanks the support from the Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area,GDZX2301005.
文摘Following the experimental realization of Quantum anomalous Hall(QAH)effect in thin films of chromium-doped(Bi,Sb)2Te3,enhancing the work temperature of QAH effect has emerged as a significant and challenging task.Here we demonstrate monolayer TbCl as a promising candidate to realize the room temperature QAH effect.Using DFT+U method,double-checked by HSE06 and DMFT calculations,we identify the Hall conductivity G=−e^(2)/h per layer in three-dimensional ferromagnetic insulator TbCl,which is a weakly stacked QAH layer.The monolayer TbCl inherits the magnetic and topological properties,exhibiting the QAH effect with Chern number C=−1.The large topological band gap reaches 42.8 meV,which is beyond room temperature.The extended 5d electrons lead to sizable exchange and superexchange interactions,resulting in a high Curie temperature T_(c)-457 K.All these features demonstrate that monolayer TbCl will provide an ideal platform to realize the room temperature QAH effect.
